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  <title>Document</title>
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  <script>
    // 1. 利用箭头函数来求和
    // const res = (...rem) => {
    //   let sum = 0
    //   rem.map(function (item) {
    //     sum += item
    //   })
    //   return sum
    // }
    // res(1, 2, 45, 6)
    const res = (...rem) => {
      let sum = 0
      for (let i = 0; i < rem.length; i++) {
        sum += rem[i]
      }
      console.log(sum);
    }
    res()
  </script>
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